Memory provides data storage for electronic systems. Flash memory is one type of memory, and has numerous uses in modern computers and devices. For instance, modern personal computers may have BIOS stored on a flash memory chip. As another example, it is becoming increasingly common for computers and other devices to utilize flash memory in solid state drives to replace conventional hard drives. As yet another example, flash memory is popular in wireless electronic devices because it enables manufacturers to support new communication protocols as they become standardized, and to provide the ability to remotely upgrade the devices for enhanced features.
NAND may be a basic architecture of integrated flash memory. A conventional NAND configuration 500 is shown in FIG. 1 in cross-sectional side view and schematic view. The NAND configuration 500 corresponds to pipe-shaped bit cost scalable (P-BiCS) flash memory. The NAND string is U-shaped and extends between a source line and a bitline. The NAND memory includes control gates 512 which are spaced from a channel region 514 by gate dielectric 516.
The channel material 514 comprises semiconductor material; and may, for example, comprise polycrystalline silicon. There may be advantages to utilizing channel materials having specific crystalline textures, but difficulties are encountered in reproducibly forming desired crystalline textures within the U-shaped channel material 514. It would be desirable to develop architectures having desired crystalline textures within U-shaped NAND channel material, and to develop methods of forming such architectures.
The NAND configuration 500 is one of many configurations in which it would be useful to tailor crystalline texture within a semiconductor material. It would also be desirable for the new methods to be applicable for other configurations in addition to the U-shaped NAND configuration 500.